Since Alzheimer's Disease remains a uniquely human illness, both AD patients sand their tissues are needed for research studies. The Clinical- Pathological Core will provide this service for Program Project Investigators by meeting the following Specific Aims. In Specific Aims 1 and 2, 40 new African-American and 40 new White AD patients and their families will be identified and recruited for participation in Dr. Haley's Project and for participation in longitudinal evaluations. In addition, two populations, i.e., 83 AD, depressed and normal controls recruited between 1987-1990, and 43 African-American demented patients followed by Dr. Haley, will continue longitudinal evaluations to characterize their neurological, psychiatric and neuropsychological functions. As many of these patients are quite severely impaired, in-home or nursing home examinations are proposed. In Specific Aim 3, a new neuropsychological battery for severely impaired patients will be developed and validated on the populations followed in Specific Aim I. In Specific Aim 4, data collected on the clinical populations will be managed and analyzed via the Data Management Unit. In Specific Aim 5, autopsies will be sought on all Program Project subjects and the mechanisms to bring these subjects to autopsy continued. In Specific Aim 6, all brains will undergo a standardized dissection, with neuropathological diagnosis performed, to be distributed to or stored for Program Project Investigators. In Specific Aim 7, analyses of presynaptic markers (SAP90, SAP97) in human hippocampus will performed in conjunction with Project 3.